Tire inflating and brake operating mechanism



Feb. 21, 1939. R. s. SANFORD I TIRE INFLATING AND BRAKE OPERATING MECHANISM Filed Sept. 2'7, 1935 (on! flressue:

F JETra/z 1 flmvmn; Rm 5. 5ANFORD' Patented Feb. 21, 1939 i UNI-TED STATES PATENT OFFICE 'rran mmrmc am) BRAKE orsaa'rme MECHANISM Roy S. Sanford, New York, N. Y., assignor to Bendix Products Corporation, South Bend, Ind., a corporation of Indiana Application September 2'1, 1935, Serial No. 42,421 5 Claims. (01. 188-110) This invention relates to safety features for Referring nowto the drawing, numeral in repautomotive vehicles and is particularly applicable resents a tire mounted in the customary fashion to large vehicles such as busses and trucks, et upona wheel l2, which wheel is rotatably mountcetera. ed upon the conventional front spindle l4 integral An object of the invention is to eliminate to a with the steering'knuckie it. An air line l8 ex- 5 large extent the hazard created by rapid deflation tends from the tire valve to the hollow hub cap in a front tire of such vehicle, as when a front 22 of the wheel which. in Combination W h a tire is punctured or blown out. By reason of the washer 24 held under the spindle nut 26 and a weight of such large vehicles rapid deflation in one resilient ring or packing gland 28 positioned in o of the front or steerable tires creates a heavy drag the hub cap, forms a rotatable leak proof conm on the steering gear which in many-instances is nection with a drilled passage 30 in the spindle. difficult for the driver to overcome. Myinven- This drilled passage terminates in a boss 32 to tion provides for the reduction in air pressure in which is secured one end of a flexibleconduit 34, both front tires if one tire develops a leak, in this the other end of said conduit bein o ect d t 5 way counterbalancing theleakage to a substantial a three-Way fitting extent and somewhat equalizing the drag on the Conduit 34 extends to said fittin rom the steering gear. other steering knuckle in the same manner as de- Animportant feature of the invention, and one scribed v and the third P 01 the threeassociated with the object above specified, resides way fi in is on c e to a w pr u an 38 20 in the arrangement whereby the pressurein one through at d p and Shut Valve which tire counterbalances that in the opposite tire at y be Positioned in y eehvenleht location and all times. In this way equalization of pressures wh ih i manually p r hrou h h ii. in the tires is assured at all times and unequal A pressure sensitive valve 44 is connected to wear by virtue of haphazard inflation of one or the low pressure tank through a conduit 46. The

25 both of the tires is to a large. extent eliminated. low p s u e ta is also in communication with 25 Itwill be apparent that by virtue of this equalia high pressure reservoir 48, the pressure in which zation of pressure at all times any given leakage ay be mai ta ned i Suitable fashion. as y a from one tire will take twice as long to deflate the compressor 0! e Vehicle engine, through tire as would be the case if the pressure in the lines 50 and 52 between which is inte p a 39 other steerable tire were not available for countervalve 54 which is Provided with an Vent 3o balancing purposes. This valve is preferably located on the dash of Another major object of the invention is to the vehicle within easy leeeh 0f the drive! ahdls arrange compressed airmechanism in such manm y Operable y means 01 a lever to p ner thatit is available to apply thebrakes of the the line between the hig Pressure reservoir and 35 vehicle automatically upon deflatlon'of th tir the pressure sensitive valve or to close such line. to any predetermined pressure and also to rein- Closing movement l w functions to p the flats the tires or to prolong the period of elapsed vent 56 to communication with the pressure sensitime after development of a leak before serious t e valve through line deflation results. It is an object therefore to Where all b s fll'e'utllized Oh the Vehicle an 40 provide means to delay the efiect'of ablowout, and air line 80 may be utilized t connect the h h 40 thereby provide sufficient time to get the car unpressure reservoir with brake actuating mechader control. a nism and suitable valves associated with the air My invention may beassociated with air brakes line 60 may be coupled with the manually operable of any conventional type and the ordinary combrake pedal 62 to control the action of the brakes.

pressed air sources tilized therefor, or special However, the invention may be utilized with equal 45 mechanism may be provided and the air pressure effectiveness where mechanical brakes are inutilized to apply mechanically actuated brakes. volved. The high pressure reservoir 48 is Various other objects and meritorious features heeted to n p and Shut valve through 6011- o: th inventi ill bec m apparent, from th duit 66 and communication between said valve 84 so following description taken in conjunction with 1 a d a edu g Valve 59 8 Provided through 0011- the drawing, wherein: duit 10. Reducing valve 68 and pressure sensitive Figure 1 is an illustration, largely diagramv lv 4 are connected y Conduit matic, of the improved mechanism; and A brake actuating piston assembly is indicated Figure 2 isa. plan view along line 2-4 of Figat 14, the piston rod having a one-way connection (,3 ure 1. with the brake pedal 62 by means of the pin and valve n, in other words the pressure in the tires and low pressure reservoir ll, falls below a predeterminedvalue The reducing valve ll includes a double spool valve II which is seated upon a coil spring II, the other end of which spring seats upon the extremity oi the valve casing. The strength O4 is such that when the pressure in the and low pressure ruervoir falls below said predetermined value, or any predetermined value, thespool valve I: 1; moved upwardly to establish or course, such communiestablished when the open in the position illustrated, oi!

operation oi the saiety mechanism will be apparent from the foregoing description. when er tire develops the air in the other tinsis automatically utilised to equalize the presin the two by reason oi the air line maintaining constant communication between the two. alumingthstthevalvellisinopenpositionas illlltrated. the pressure sensitive valve 44 will Opsratewhen thepiessureinthetireshasiallen toapredcterminedvaluetoestablishcommunicatimbetweenthehishpressuretankssandthe actuating pistonassembly'll toimmediatethebrakes. Itwillbeapparentthatthe lloithepressm'esensitivevalvemaybe than spring ll in reducing valve is, and such ielga tionoithsvehiclesolongastheleak enttorequiregreater replacement pressure tank could conveniently the high pressure tank was extoorapidlybecauseoithesiseoitheleak, the pressure sensitive valve ll would function as hithertodescribed to applythe brakes and stop the vehicle. At thesame time communication or the ishprsssuretanktothetirewouldbeshut oflbyaie automatic closingoitheopenand shut valve in release the brakes when so automatically appliedbythepressuxeinthehighpressuretank honlynecessarytomovethelever lltothe l'llhti'orthepurposeoiventingpistonassembly ll to'airthmughvent ,at the same time clospassagebetweenthehishpressure said piston amembly. when the tinhasbsenchangedtheleverllmaybeagain Ilovedtothepoaitioniilustratedinthedrawing,

arcane the brakes having been released, and the high pressure tank 4| may be utilized to reinflate the tires through lines I, II, and reducing valve ll. Where, under emergency conditions, it seems preferable to utilize the high pressure tank to maintain inflation oi the tire as long as possible rather than to utilise said tank for applying the brakes, the lever ll of valve ll may be shifted to the right when the leakage or blowout occurs, thereby preventing operation of the piston assembly I4 and maintaining communication through line II between the high pressure tank and the tires.

While certain mechanism for accomplishing the desired functions has been illustrated in the accompanying drawing, various modifications will be apparent to those skilled in the art and for that reason I wish to limit the invention only by the scope oi the appended claims.

I claim:

1. In combination with a vehicle having a plurality oi road engaging pneumatic tires, normally open air lines providing communication therebetwcen to equalize the pressures therein, a pressure tank, brake applying means, actuating means coupled with said brake applying mechanism and said tank for operating the former, and means comprising a spring loaded floating valve member operable on deflation oi said tires below a predetermined value for rendering said actuating means operative.

2. In combination with a road engaging pneurnatic tire and a brake mechanism, a pressure tank, and means comprising a spring loaded floating valve member and means operable by said brake mechanism, operable on deflation of said tire below a predetermined value to establish communication between said tank and said tire to bring the inflation pressure back to said predetermined value.

3. In an automotive vehicle provided with a road chilling pneumatic tire and brake applying mechanism, means for maintaining the inflation pressure of said tire above a predetermined amount and for actuating said brake applying mechanism in the event the inflation pressure is lowered to a predetermined amount, said means including a pressure tank, fluid transmitting means interconnecting said tank and tire. a pressure sensitive valve and a reducing valve connected in series in said fluid transmitting means, one oi said valves being automatically operable, when the inflation pressure reaches a predetermined amount, to eflect an operation of said brake applying mechanism.

4. In an automotive vehicle provided with a road engaglnl pneumatic tire and brake applying mechanism including a pressure diflerential operated motor, means for maintaining the inflation pressure 0! said tire above a predetermined value and for actuating said brake applying mechanism in the event the inflation pressure is lowered to a predetermined amount, said means including a pressure tank, fluid transmitting means interconnecting said tank and tire, a pressure sensitive valve and a reducing valve connected in series in said fluid transmitting means, one oi said valves being automatically operable. when the inflation pressure reaches a predetermined amount, to eflect an operation of said pressure diflerential operated motor to apply the brakes, together with manually operable valve means operable to deenergize said motor to elect a release of the brakes.

5. In an automotive vehicle provided with a road engaging pneumatic tire and brake applying pressure reaches a predetermined amount, to

mechanism, means for (1) maintaining the inflarender the first-mentioned means operable to tion pressure within said tire at or above a premaintain the inflation pressure at or above a determined amount in the event of a blow-out predetermined amount, and further including a 5 of said tire and (2) automatically applying the pressure sensitive valve automatically operable I brakes of the vehicle should said inflation presat a predetermined inflation pressure oi! the tire sure drop to or below a predetermined amount, to eflect an operation of the first-mentioned said means including a power means for applymeans to apply the brakes oi the vehicle. ing the brakes and Iurther including a reducing 10 valve automatically operable, when the inflation ROY S. SANFORD. 10 

